Using the REA approach to developing a database for an accounting system, you have identified one event, or activity, that needs to be included in the database. The event is a purchase from a vendor. The organization makes over-the-counter purchases in which the purchasing agent makes a purchase and immediately receives the goods purchased. All purchases are on account, and the company uses a voucher number to uniquely identify all purchases. Required: a. Identify any resources and agents that are related to the purchase event. Document the event and any resources and agents with an E-R diagram. b. Identify the relationship among the events, resources, and agents. Add these relationships to your E-R diagram. Indicate on your E-R diagram the type of each relationship that is, 1:1,1:*, *:1, or *.*. c. Identify and list the attributes that are related to the resources, events, agents, and relationships. d. Create the appropriate database tables by referring to the E-R diagram.